In various communication systems, such as in wireless or cable communications, a receiver processes a broadband signal such as a multi-channel signal.
Methods for processing broadband signals are known in the art. For example, an article titled “Polyphase Filter Banks for Embedded Sample Rate Changes in Digital Radio Front-Ends,” ZTE communications, December 2011, volume 9, number 4, which is incorporated herein by reference, describes processing engines for Software-Defined Radio (SDR) front-ends. These engines, which are based on a Polyphase channelizer, perform arbitrary sample-rate changes, frequency selection, and bandwidth control. The article presents an M-path Polyphase filter bank that is based on a modified N-path Polyphase filter. Such a system allows resampling by arbitrary ratios while performing baseband aliasing from center frequencies at Nyquist zones that are not multiples of the output sample rate.
U.S. Pat. No. 7,394,871, whose disclosure is incorporated herein by reference, describes a digital multi-channel demodulator circuit. The demodulator includes a frequency-block down-converter that shifts a received multi-channel analog RF signal to a lower frequency band. An Analog to Digital Converter (ADC) receives the multi-channel analog RF signal from the frequency-block down-converter and converts the multi-channel analog RF signal to a multi-channel digital RF signal. A digital channel de-multiplexer receives the multi-channel digital RF signal from the ADC and de-multiplexes the multi-channel digital RF signal into separate digital RF channels.